depopulation
    n 1: the condition of having reduced numbers of inhabitants (or
         no inhabitants at all)

Depopulation \De*pop`u*la"tion\, n. [L. depopulatio pillaging:
   cf. F. d['e]population depopulation.]
   The act of depopulating, or condition of being depopulated;
   destruction or explusion of inhabitants.
   [1913 Webster]

         The desolation and depopulation [of St.Quentin] were
         now complete.                            --Motley.
   [1913 Webster]

DEPOPULATION. In its most proper signification, is the destruction of the 
people of a country or place. This word is, however, taken rather in a 
passive than an active one; we say depopulation, to designate a diminution 
of inhabitants, arising either from violent causes, or the want of 
multiplication. Vide 12 Co. 30.